Such a tape is known from Netherlands patent 1003851 of applicant, and is applied particularly for closing cavity channels of double-walled plastic plate material in dustproof yet ventilating and water-permeable and water vapour-permeable manner. The tape comprises an elongate strip of fabric in which or on which is arranged a pattern which completely closes the pores locally so as to thus enable the degree of ventilation to be regulated precisely and as required. The pattern can be a pattern of compacted parts which is arranged mechanically in the strip itself under pressure and at increased temperature, or a coating with which the strip is covered according to the desired pattern.
Although a very satisfactory product can hereby be realized which is highly adaptable to the specific wishes of a customer, it does have the drawback that arranging of the pattern always requires an additional process step and thereby increases the cost price of the product.